This invention relates to airplanes and more particularly to airplane ground maneuvering systems.
As airplanes get larger, the distance between the main landing gear and nose landing gear (i.e., wheelbase and distance between each main landing gear (track)) becomes greater. As a result, turning maneuvers require more space. Because most airports were constructed to handle smaller, more maneuverable airplanes with shorter wheelbases and tracks, large airplane maneuvering becomes even more difficult. The restricted widths of the runways and taxiways, coupled with greater airport congestion, have made it progressively more difficult for pilots of large commercial airplanes to make tight maneuvers. Maneuvering large airplanes is difficult because of a lack of feedback to the pilots about relative positioning of the landing gear on the ground. The lack of feedback occurs because an airplane""s landing gear are located beneath the fuselage or wings. Accurate knowledge of the location of landing gear, specifically the tires and wheels of the landing gear, is particularly important when maneuvering in tight spaces at crowded airports. A pilot""s ability to see runway and taxiway edges, ground service vehicles and potential obstructions is also very limited in large airplanes.
In smaller airplanes, pilots steer the airplane such that the cockpit of the airplane remains over a painted nosewheel guideline or the estimated nosewheel location remains over the nosewheel guideline while executing taxiway-to-taxiway turns. Pilots of large airplanes typically use xe2x80x9cjudgmental oversteering,xe2x80x9d deliberately making the nosewheel follow a path outside of the nosewheel guideline, thereby reducing the probability that the wheels of the inside turning main landing gear will run off of the pavement or hit edge lights, flags or signs. Precise control of judgmental oversteering is prone to error and to occasional incidents of wheels running off the runway/taxiway and causing damage to the airplane or to ground installations in large airplanes with large distances between the pilot and the main landing gear.
One method for lessening the chances of the above-mentioned oversteering problems occurring is the addition of large radius airplane nosewheel guidelines that are offset relative to existing centerline-to-centerline faired circular arc guidelines. Because this method is airport-dependent rather than airplane-dependent, it has the potential disadvantage of misguiding small airplanes.
Large airplanes with long wheel bases and wide main gear track also face challenges in other types of ground maneuvers such as gate entry maneuvers and runway or turnpad U-turn maneuvers.
The present invention provides a system for aiding the maneuvering of airplanes. The system includes at least one, and preferably several, cameras for generating video images. The camera(s) is mounted on the airplane so that it can simultaneously view at least one landing gear, preferably a main or nose landing gear, and the ground surrounding it to allow the pilot to safely steer the airplane. The system also includes a video display within the cockpit of the airplane for displaying the generated video images and a user interface for selecting the timing and optionally the format for displaying the generated video images.
In accordance with other aspects of this invention, a camera is mounted on the belly, and/or on the horizontal or vertical stabilizer of the airplane. The belly-mounted camera is positioned either between the nose landing gear and the two main landing gear, between the tall of the airplane and the two main landing gear, forward of the nose landing gear or under a wing of the airplane.
In accordance with further aspects of this invention, a camera is mounted on a movable device located within a moveable component of the airplane. The movable device compensates for component movement, such that the generated video images are substantially unaffected on the display screen when the component moves.
In accordance with still other aspects of this invention, the system includes an image motion compensation processor and a display generator for aiding the ground maneuvering of airplanes with wide wheel tracks, long wheelbases, or both. The image motion compensation processor determines the airplane""s position with respect to airport surface markings and equipment displayed within the displayed video images. The display generator generates and displays a superimposed oversteer target on the displayed video images based on the determined airplane position with respect to airport surface markings and equipment. The oversteer target may also be the corner or edge of a carefully selected field of view. The airplane is properly oversteered and executes a guided oversteer turn when the oversteer target is directed by the pilot to track along a painted nosewheel guideline or centerline which is visible on the display. The display generator also generates and displays superimposed images on the displayed video images for identifying the location of the main landing gear of the airplane, the lateral clearance of airport surface markings and equipment, and the contact point of the landing gear wheels and the airport surface.
In accordance with still further aspects of this invention, the cockpit display device presents video images from multiple cameras in a split-screen format or allows pilots to select views individually.
As will be readily appreciated from the foregoing summary, the invention provides a system for allowing pilots to accurately steer large airplanes during taxiway to taxiway turns, U-turns, and gate maneuvering turns. Thus, this system reduces the chances of large airplanes maneuvering off the designated taxiway or runway, into ground service vehicles, ground personnel or into ground installations. This system can also provide visibility of turnaround activities.